A literature survey of published single-droplet drying models has exposed their various shortcomings. An advanced theoretical model of drying of single droplets, containing either insoluble or dissolved solids, has been developed and numerically solved. The validation of the developed model has been accomplished by comparison of the predicted temperature and mass histories with published experimental data for slurries of silica and skim milk solution under different conditions. The results of simulations showed a good agreement between the calculated curves and experimental points in all case studies.

During the last decades, growing attention has been given to theoretical and experimental studies of drying behavior of single droplet containing solids. This research interest is motivated by the need for fundamental understanding of the drying phenomena in extensively used technological processes like spray drying, fluidized bed drying, pneumatic drying, etc., at drop-wise and particulate levels. The present literature review summarizes the developed theoretical models of single droplet drying kinetics, discovers their benefits and deficiencies, and identifies prospects for future research.